Earthmoving and construction machines, such as track-type tractors, utilize multiple disc steering clutches and brake assemblies for steering and braking the machine. These multiple disc assemblies include a plurality of rotatable and complimentary non-rotatable discs which contact each other when the machine is in operation and or is being braked. A large quantity of fluid is supplied to these disc assemblies for lubrication and cooling. During a braking operation, when the rotating discs contact the non-rotating discs, considerable heat is generated from the frictional engagement of the brake discs. A large quantity of fluid is directed to the brake discs to cool the discs and prevent warping and damage.
When the brakes are released and the rotating discs separate from the non-rotating discs, the lubricating and cooling fluid is normally continuously supplied to the brake assembly. This produces what is generally referred to as "brake drag" and is a result of large amounts of cooling fluid meeting with the rotating brake discs. This "brake drag" decreases the overall efficiency of the machine and subtracts from the power transmitted between the engine and tracks of the vehicle. Extra oil being pumped through the brakes also reduces efficiency by taking more engine power to drive the oil pump.
The present invention is directed to overcoming one or more of the problems as set forth above.